1. Technical Field
The disclosure relates to a technical field of a power supply control system installed on a vehicle, such as a hybrid vehicle.
2. Description of Related Art
As one example of this type of system, a system that controls charge/discharge of a battery installed on a vehicle is known. According to a technology proposed in Japanese Patent Application Publication No. 2007-318913 (JP 2007-318913 A), for example, when a battery voltage detected when discharge is started after regenerative power generation is higher than a predetermined value, it is determined that the amount of charge of the battery is larger than a target value, and the amount of discharge is controlled to be larger than an integrated value of current obtained through the regenerative power generation. When the battery voltage is lower than the predetermined value, it is determined that the charge amount of the battery is smaller than the target value, and the discharge amount is controlled to be smaller than the integrated value of current obtained through the regenerative power generation.
According to the technology described in JP 2007-318913 A as described above, when the battery is discharged, generated voltage of an alternator serving as a generator is controlled to be reduced. However, if the generated voltage is reduced excessively relative to the OCV (Open Circuit Voltage) of the battery, for example, the absolute value of current delivered from the battery is increased, which may result in reduction of the lifetime of the battery. Thus, when the generated voltage of the generator is controlled, it may be considered, as a technical problem, that the lifetime of the battery is reduced due to unintended increase of charge/discharge current.